A valve which is mounted for use on a piping base member by using an elastic force of a mounting lever is known, for example, as disclosed in Patent Literature 1 and Patent Literature 2. The valve includes a pair of mounting levers on opposite side surfaces of a valve body in which a valve mechanism for opening and closing a fluid flow path is housed, so that a first mounting lever which is one of the pair is formed to be elastically deformable and a second mounting lever which is the other of the pair is not elastically deformable.
When the valve is mounted on the base member, an operation section on one end of the second mounting lever is strongly pressed by a finger toward the side surface of the valve body so as to elastically deform the second mounting lever to increase a distance between both mounting levers. Then, an engaging section of a protruding shape on the distal end of the first mounting lever of the opposite side is forced to engage in an engaging groove formed on one side surface of the base member, and then, an engaging section on the distal end of the second mounting lever which is elastically deformed is placed in an engaging groove formed on the other side surface of the base member. Then, elastic deformation of the second mounting lever is released so as to allow the engaging section to be engaged in the engaging groove, thereby allowing the engaging sections of the pair of mounting levers to be engaged in the engaging grooves of the base member.
When the valve is removed from the base member, an operation is performed in the opposite way to that of mounting.
The known valve is advantageous in that it can be mounted on the base member without using a screw. However, since only the second mounting lever which is one of the pair of mounting levers is elastically deformed when the valve is mounted on the base member and removed from the base member, an extent of the elastic deformation needs to be increased. Further, in order to prevent the valve mounted on the base member from being inadvertently removed due to vibration or collision, the mounting lever is formed to have a certain degree of rigidity so as not to be easily elastically deformed. As a result, a significantly large force is required for attaching and removing operation, which causes some difficulties in operationability.
In Patent Literature 3, a valve is disclosed which is configured such that both of a pair of mounting levers are elastically deformable. When the valve is mounted on the base member, a distal end of the pair of mounting levers is placed on the base member from above, and then the valve is straightly downwardly pressed down so that the pair of mounting levers are forced to be apart from each other by the base member. After the engaging sections on the distal ends are elastically fitted and engaged in the engaging grooves on both side surfaces of the base member, the pair of mounting levers recovers so that valve can be mounted on the base member in a snap-fit manner.
However, when the valve is removed from the base member, the operation sections of the pair of mounting levers need to be held by both sides by fingers and deformed in a direction in which they are brought close to each other so that both of the pair of mounting levers are simultaneously elastically deformed to increase a distance between the engaging sections on the distal ends for removing the engaging section from the engaging grooves of the base member. As a result, similar to the valve disclosed in Patent Literature 1 and Patent Literature 2, a significantly large force is required for deformation operation, which causes some difficulties in operationability.